Dan Johnson is the Chair of the Geography Department at IUPUI. He specializes in climate change and its impact on human health especially those of vulnerable populations. His work includes modeling and developing systems that provide early warning for cities during extreme heat events and extreme precipitation events. These activities are currently ongoing in a number of U.S. cities. He actively works with the United States Centers for Disease Control and Prevention and NASA. Source: http://www.urbanhealth.iupui.edu/executiveCommittee.aspx?id=26